Elbow epicondylitis is a painful condition caused by overuse and development of tendon degeneration. It is one of the most common elbow problems in adults, occurring both laterally and medially. “Tennis elbow” or lateral epicondylitis is diagnosed 7 to 10 times more often than the medial form, “golfer’s elbow.”1 Although these injuries are often associated with racquet sports, activities such as bowling and weightlifting and the professions of carpentry, plumbing, and meat-cutting have been described as causes.2,3
Elbow epicondylitis is thought to be the result of multiple microtraumatic events that cause disruption of the internal structure of the tendon and degeneration of the cells and matrix.4 Lesions caused by chronic overuse are now commonly called tendinosis and are not considered inflammatory in nature. Although the term tendinitis is used frequently and indiscriminately, histopathologic studies have shown that specimens of tendon obtained from areas of chronic overuse do not contain large numbers of macrophages, lymphocytes, or neutrophils.5 Rather, tendinosis appears to be a degenerative process that is characterized by the presence of dense populations of fibroblasts, vascular hyperplasia, and disorganized collagen. This constellation of findings has been termed by some authors as angiofibroblastic hyperplasia.6
Conservative care for the treatment of chronic tendinosis has been well described and is often successful. Treatment consists of rest, ice, compression, and elevation in the acute phase. This can be followed with bracing, activity modification, physical therapy, oral nonsteroidal anti-inflammatory drugs, topical applications, and injections of cortisone or platelet-rich plasma. When conservative treatment fails, surgical intervention may be considered. Procedures for the treatment of lateral epicondylitis include open débridement and release, arthroscopic débridement, percutaneous release, and radiofrequency (RF) coblation. The goals of operative treatment are to resect pathological material, to stimulate neovascularization by producing focused local bleeding, and to create a healthy scar while doing the least possible structural damage to surrounding tissues.4
The efficacy of a bipolar RF-based approach for using microtenotomy was first recognized when researchers studied the effects of transmyocardial revascularization for treating congestive heart failure.7 The use of RF- and laser-based transmyocardial revascularization initiated an angiogenic response in degenerated (ischemic) heart tissue. This success led to investigating the use of a RF-based approach for performing microtenotomy. Preclinical studies demonstrated that RF-based microtenotomy was effective for stimulating an angiogenic-healing response in tendon tissue.8 Histologic evaluation of treated tendons showed an early inflammatory response, with new blood-vessel formation by 28 days. In 2005, short-term results of this technique were published.9 This preliminary prospective case series showed that the treatment was safe and effectively improved or eliminated clinical symptoms.9 In the present midterm study, we hypothesized that pain scores would improve after RF microtenotomy and that these favorable results would continue to be observed over a longer term postoperatively.
Materials and Methods
Patients
This was a prospective, nonrandomized, single-center clinical study. After receiving institutional review board approval, patients who were 18 to 65 years of age with a diagnosis of tendinosis were approached for enrollment. For inclusion, patients had to be symptomatic for at least 6 months and had to have failed extensive conservative treatments. Nonoperative treatment included activity modification, enrollment in a facility- or home-based exercise program, bracing, oral nonsteroidal anti-inflammatory medication, and cortisone injection. Candidates with diabetes, confirmed or suspected pregnancy, surgery in the same tendon, implanted hardware adjacent to the target treatment region, or who were receiving care under workers’ compensation or had litigation-related injury were excluded. A single clinician performed a thorough medical history and clinical evaluation. The clinical follow-up and data collection were performed by an independent medical technician.
Clinical Outcomes
Pain status was assessed by using a visual analog scale (VAS). Postoperative clinical assessment was conducted within the first 2 days; at 7 to 10 days; at 4 to 6 weeks; and at 3, 6, 12, and 24 months, up to 9 years postoperatively. The VAS scales were completed annually up to 9 years after the procedure.
The percent improvement of VAS score was calculated. This value represented the difference between the patient’s preoperative and most recent VAS assessments. Failure of the procedure was defined as less than 50% improvement of the VAS score.
The RF-Based Microtenotomy Device
The Topaz Microdebrider (ArthroCare), connected to a System 2000 generator at setting 4 (175 V-RMS), was used to perform the RF-based microtenotomy. The device uses a controlled plasma-mediated RF-based process (coblation). Radiofrequency energy is used to excite the electrolytes in a conductive medium, such as a saline solution, to create precisely focused plasma. The energized particles in the plasma have sufficient energy to break molecular bonds,10,11 excising or dissolving (ie, ablating) soft tissue at relatively low temperatures (typically, 40°-70° C).12,13 The diameter of the active tip of the Topaz device is 0.8 mm.